238 



SCIENCE-GOSSIP. 



[Oct. 1, 1865. 



Ichneumons and Vanessa. — In your January 

 number, p. 15, "The Entomologist" says that the 

 "small Tortoiseshell Butterfly" is free from_ ich- 

 neumons. I send you a paper, the inside of whicli is 

 completely eaten out by them, also one of the flies 

 which crawled out of it, and some empty ichneumon- 

 cases wbicli I found close by. This is the second I 

 have found in the same place. — U. W. 



Wasps. — In Greece, a large wasp, marked on tb. 

 abdomen with alternate rings of black and yeilow, 

 is very fond of grapes, and therefore a foe to the 

 gardener, who gives them no quarter. It sucks the 

 juices from the grape as soon as it is ripe, leaving 

 nothing but the seed and shrivelled skin. This wasp 

 also destroys numbers of spiders, which it treats 

 like the grapes, rejecting the epidermis. Many 

 severe and protracted combats ofttimes take place 

 before the spider yields to its more powerful anta- 

 gonist. I have observed that in pursuing spiders, 

 the wasp rarely flies, but almost invariably runs after 

 its prey. It attacks spiders without reference to 

 size, and kills them by stinging. Does this happen 

 in England ?— /. B. Ilcnj, Athens. 



BiBDs' Eggs. — Some time since, while searching 

 for birds' eggs, I found a Catbird's {Turdus avidtis) 

 nest, containing two_ fidl-sized eggs, and a third, 

 similar to the others in colour, only of the size of a 

 pea. How to account for this I know not. But it 

 is well known that hens often lay eggs much smaller 

 than the average size, sometimes not larger than a 

 robin's ; may not birds do the same ? This is the 

 only case which has occurred to my knowledge. 

 Have any sucli instances occurred in England ? — 

 /. B. Hay, AtJiens. 



BiiACK Beetles.— Eor the information of "A. H.," 

 I send you the following method of destroying 

 tlicni, which 1 have found more effectual than any 

 of the advertised remedies :— Take one or more 

 shallow glazed dishes (say three or four inches deep), 

 and about half till them with common beer, or warm 

 water with a little ginger or nutmeg grated in to 

 make it smell ; a little treacle also is a good thing. 

 Place the dishes in their haunts, and put some bits 

 of wood or something against the sides of the dislies 

 for them to creep up (paper will not answer, as the 

 noise of running up it appears to alarm them). The 

 beetles and crickets being very thirsty creatures, 

 and always ready for their " drops," get into the 

 liquor and cannot get out again.—/. Goodyear. 



Guide to the Conservatory. — A. H. wishes 

 to know a book for the careol a "conservatory," 

 containing what flowers are the best to plant in pots 

 and vases, so as to keep up a succession of flowers 

 all through the year. How hot should a conserva- 

 1ory be kept during autumn and winter? Please 

 state the price of book. 



Black Ants.— Under July 24tli, I have a note 

 111 my pocket-book to the effect that I noticed on 

 that day a number of large black ants crawling 

 f!b<mt the streets of Camberwell and Kenningtou. 

 I should like to know whether any one noticed the 

 same in any other part of London, and what was the 

 canso, of \t.—W. li. Tate, 4, Grove Place, Denmark 

 hill. 



PoDURiE Phosphorescent. — Is it known that 

 any species of the genus Podura (Linn.), order 

 Thysanaura (insecta), is capable of emitting a phos- 

 phorescent light? 1 have good reasons for believing 

 that one which I have met with is so capable. The 

 head has a vertical movement, the centre of motion ; 

 tail about two-thirds length of body ; compact, 

 silvery-white skin ; slight annular markings on back. 

 If worth while, I can supply live specimens and 

 further particulars. — //. 31. 



Pollen oe Valerian. — Have any of your readers 

 observed hov/ beautiful the pollen of Valerian is ? if 

 not, I advise them to do so. It requires rather a 

 high power.^F". Gibson. 



Diameter of Lenses. — Can any of your readers 

 oblige me with the diameter of the compound lenses 

 used in making -^-inch object-glass, and the focus of 

 each compound lens in it, and the diameter of the 

 aperture 'i—E.T.S. 



Parasites op Parsnip. — The leaves of the wild 

 parsnip are very much mildewed ; but, besides the 

 usual round conceptacles, there are some others, 

 consisting of an immense number of transparent 

 bodies in shape very much resembling the blade 

 of a reaping-hook. What is their name and 

 purpose, as I don't see them mentioned by M. 

 C. Cooke in tbe papers on fungi in Popular Science 

 Reoieio.—R T. S. 



[Specimens should have been sent. — Ed.] 



A New Silene.— I extract the following from 

 the Guardian of August 23rd : — " A specimen of a 

 new plant, the Silene dichotoma, has been found 

 near Painswick, Gloucestershire. It is a native of 

 south-eastern Europe, and must have been intro- 

 duced accidentally." Can any of your readers give 

 me any additional information regarding the appear- 

 ance of this " distinguished foreigner " in this 

 counti'y ? — B. 



Appendages to Water Beetles.— I have fre- 

 quently observed on male specimens of Dytisciis 

 marginalis (both alive and dead) a quantity of pear- 

 shaped excrescences firmlrattached by "the small end 

 to the uuderpart of the head of the insect. These 

 excrescences are of a blood-red colour, and when 

 squeezed, a red liquid exudes. Can you, or any of 

 your correspondents, tell me what they are ? — 

 E. liagonot. 



Volvox Glorator. — Will you kindly allow me 

 to say, in answer to T. P. Barkas's reply to my 

 query, I am quite aware that it is generally stated 

 the motions of the Volvox Globator are caused by 

 the action of cilia ; but I have examined some thou- 

 sands in every stage, and have been unable really 

 to observe cilia ; and many of my microscopic friends 

 have also studied it, and none of them have been 

 more successful than I have. I was in hopes my 

 query would have drawn a reply from some one who 

 had also devoted some time in examination of this 

 very beautiful and interesting microscopic object, 

 and who could, from observations, give a new tlieory 

 respecting the cause of its revolutions. T. P. 

 Barkas's remarks are really not a reply to my ques- 

 tion. A great many of your readers are, I know, 

 equally interested as myself in this, and quite as dis- 

 appointed that my query has not drawn forth a better 

 reply to it.— -Thomas Armstrong. 



